Dayco XTX2244 XTX Extreme Torque ATV/UTV Drive Belt Fits 09 and newer Polaris 550, 850cc models and replaces OEM #: 3211123 Length: 39.500 inch Width: 1.240 inch Faster and more consistent throttle response at high speeds, Quicker throttle response at mid-speed acceleration. Greater secondary acceleration at high RPMs, Reduction in slippage during the highest levels of torque Increased horsepower capacity, better performance during deceleration (more responsive engine braking) Tested and proven reliable at well over 12,000 RPMs with cooler running than the leading competitors This race-tested Dayco XTX belt gives extreme riders the best out-of-the-hole acceleration, throttle response and durability, for the ride of a lifetimeevery time